Bloodwork Basics

Lp(a), Fasting Insulin, Cortisol and More: What the Ultimate Panel Markers Add

Lipoprotein(a), fasting insulin, cortisol, ferritin, and prolactin each answer a question a standard panel leaves open. Learn what they measure, what they can't tell you, and how to prepare for the draw.

By BloodWorx TeamPublished

A standard blood panel is built to answer common questions: are the major organ markers in range, how are cholesterol and blood sugar trending, is there anything obvious in the blood count. That is a useful baseline. It also leaves some specific questions open — ones that serious trainees and health-conscious adults tend to ask sooner or later.

Our Ultimate panels now include several markers aimed at those gaps. This guide explains what each one measures, why it adds information a basic panel does not, and what it cannot tell you on its own.

Marker Men’s Ultimate Women’s Ultimate
Lipoprotein(a) Included Included
Fasting insulin Included Included
Cortisol — Included
Ferritin Included Included
Prolactin Included Included

Lipoprotein(a): the inherited heart-risk marker

Lipoprotein(a), usually written Lp(a), is a cholesterol-carrying particle similar to LDL with an extra protein attached. Elevated Lp(a) is considered an independent risk factor for atherosclerotic cardiovascular disease and for aortic valve stenosis — independent meaning it adds risk information beyond what LDL cholesterol shows.

Three things make it different from most markers on a panel:

  • It is largely set by genetics. A European Atherosclerosis Society consensus statement describes Lp(a) levels as predominantly genetically determined. Diet, training, and body composition have relatively little effect on it, so a lean, fit athlete can still carry a high level.
  • A standard lipid panel does not measure it. LDL cholesterol can look entirely unremarkable while Lp(a) is elevated. Unless someone specifically orders it, most people never learn their number.
  • It tends to be stable. Because it changes relatively little across adult life, the same consensus statement recommends measuring it at least once in every adult. Many people will not need to repeat it often, though a clinician may choose to in some situations.

The 2018 American Heart Association / American College of Cardiology cholesterol guideline lists an elevated Lp(a) as a “risk-enhancing factor” — one of the pieces a clinician can weigh when assessing someone’s overall cardiovascular risk. Results can be reported in different units (mg/dL or nmol/L), which do not convert cleanly, so it is worth comparing like with like over time.

A high Lp(a) does not mean heart disease is inevitable, and it does not prescribe a treatment by itself. It is context — often most useful alongside ApoB, a lipid panel, blood pressure, and family history. Our ApoB guide covers how those particle-based markers fit together. Because Lp(a) is inherited, a result can also be worth sharing with close relatives, who may want to discuss testing with their own clinician.

Fasting insulin: the early side of blood sugar

Glucose and hemoglobin A1c describe blood sugar. Fasting insulin describes how hard the body is working to keep it there.

When tissues respond less well to insulin, the pancreas can compensate by producing more of it. During that phase, glucose and A1c may still look normal while insulin is running higher. Measuring fasting insulin alongside glucose and A1c can therefore add context about insulin sensitivity that the glucose markers alone do not show.

A few caveats matter:

  • It needs a true fast. MedlinePlus notes that you will usually need to fast for 8 to 12 hours before an insulin test. A non-fasted insulin value is very hard to interpret.
  • Reference ranges vary between labs, and there is no single universally agreed “optimal” fasting insulin. Trends over time and the whole metabolic picture matter more than a single number.
  • It is not a diagnosis. Diabetes and prediabetes are defined by glucose-based criteria, not by insulin. Fasting insulin is supporting context for that conversation.

Cortisol: the stress-axis snapshot (Women’s Ultimate)

Cortisol is produced by the adrenal glands and helps regulate the stress response, blood sugar, blood pressure, and inflammation. It follows a strong daily rhythm: levels are normally highest in the morning and fall across the day.

That rhythm is why timing matters so much. A morning value and an afternoon value from the same person are not comparable, and typical reference ranges assume a morning draw. Stress, hard exercise, temperature extremes, pregnancy, and some medications — including birth control pills — can all raise cortisol, according to MedlinePlus.

A single morning cortisol can add context when fatigue, recovery, or stress load are part of the question. It has real limits, though. It is one moment in a hormone that changes hour to hour, and confirming or ruling out a true cortisol disorder typically requires specific follow-up testing directed by a clinician. A normal or borderline result should not be read as a verdict on how stressed you are, and “adrenal fatigue” is not a recognized medical diagnosis.

Ferritin: iron stores for everyone who trains

Ferritin reflects the body’s stored iron and is usually the first iron marker to fall as stores run low — often before hemoglobin changes on a CBC. It was already part of both women’s panels; Men’s Ultimate now includes it too, since low iron stores are not exclusively a women’s issue, particularly in endurance athletes and people with high training volumes or restrictive diets.

Ferritin also rises with inflammation, so a normal value does not always rule out low stores. Our full guide, Ferritin and Iron for Athletes, explains how to read it alongside CRP and a CBC.

Prolactin: hormone context for men, too

Prolactin is a pituitary hormone best known for its role in breastfeeding, but it matters for everyone. In men, elevated prolactin can lower sex drive, cause erectile dysfunction, and affect testicular function, which is why it is often part of a hormone workup. Women’s Ultimate has always included it; it is now standard on Men’s Ultimate as well, rather than an optional add-on.

Small increases can come from ordinary things. MedlinePlus lists stress, exercise, and even sex as possible causes of mild elevations, and several medications can raise prolactin too. A single mildly high value is therefore often rechecked before anything is concluded, and persistently high levels are a question for a clinician.

How to prepare for the draw

Because the Ultimate panels now include fasting insulin — and, on the women’s panel, cortisol — the simplest approach is:

  • Fast for 8–12 hours beforehand. Water is fine. This also sharpens the glucose and lipid markers already on the panel.
  • Book a morning appointment. It makes the fast easier and matches the timing most cortisol and hormone reference ranges assume.
  • Skip hard training before the draw. Intense exercise can temporarily raise cortisol and prolactin, and it can also affect markers like AST and ALT — see Can Hard Training Raise AST and ALT?.
  • Note anything unusual. Recent illness, poor sleep, new medications or supplements, and (for women) the date of your last period are all useful context when your provider reviews results.

Where to find these markers

All five are included in our Ultimate panels — Men’s Ultimate and Women’s Ultimate — with the split shown in the table above. Each is also available individually on the build-your-own panel page if your question is narrower than a full panel; our guide to choosing individual tests explains when that makes sense.

As with any lab result, an unexpected or persistently abnormal value is a reason to talk with a qualified healthcare professional, who can interpret it alongside your history, symptoms, and other results.

Sources & further reading

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